在Spring Integration上理解Http GET请求的正确配置的问题

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-integration</artifactId>
</dependency>

@Bean
public HttpRequestHandlingMessagingGateway httpGateway() {
    HttpRequestHandlingMessagingGateway gateway = new HttpRequestHandlingMessagingGateway(true);
    gateway.setRequestMapping(createRequestMapping());
    gateway.setRequestPayloadTypeClass(String.class);
    gateway.setRequestChannel(httpRequestChannel());
    gateway.setReplyChannel(httpResponseChannel());
    return gateway;
}

private RequestMapping createRequestMapping() {
    RequestMapping requestMapping = new RequestMapping();
    requestMapping.setMethods(HttpMethod.GET);
    requestMapping.setPathPatterns("/api/endpoint");
    return requestMapping;
}

@Bean
public MessageHandler httpHandler() {
    return new ServiceActivatingHandler(new MyHttpHandler());
}

public class MyHttpHandler {
    public String handleRequest(@Header("param") String param) {
        // 处理GET请求的逻辑
        return "Response";
    }
}

@Bean
public MessageChannel httpRequestChannel() {
    return new DirectChannel();
}

@Bean
public MessageChannel httpResponseChannel() {
    return new DirectChannel();
}

@Bean
public MessageConverter messageConverter() {
    return new StringMessageConverter();
}

@Bean
public IntegrationFlow httpFlow() {
    return IntegrationFlows.from(httpGateway())
            .channel(httpRequestChannel())
            .handle(httpHandler())
            .channel(httpResponseChannel())
            .get();
}